#include<iostream>

int main()
{
	using namespace std;

	int max_4(int a, int b, int c, int d);
	int a, b, c, d, max;
	cout << "cin 4 num:";
	max = max_4(a, b, c, d);
	cout << max << endl;
	
	return 0;

}

int max_4(int a, int b, int c, int d)
{
	int max(int, int);
	int m;
	m = max(a, b);
	m = max(m, c);
	m = max(m, d);
	return (m);
}

int max(int x, int y)
{
	if (x > y);
		return x;
	else
		return y;
}